Contents:
ARR_SWISSPROT_BG
DICT_AA20_INDEX
STR_AA20
STR_GAP_CHARS
SubstitutionPseudocounts
column_conservation()
column_counts()
column_information_content()
consurf_grade_boundaries()
consurf_grades()
henikoff_weights()
Amino acid -> index into a length-20 vector (STR_AA20 order).
dict[str, int]